commit f3a6839e5bd52540a962198d44328784e3a7c6ec
author Andrew Walbran <qwandor@google.com> Wed Jan 15 14:18:04 2020 +0000
committer Andrew Walbran <qwandor@google.com> Thu Jan 23 10:53:45 2020 +0000
tree 098a6a62f44b17b68c6e888f62ea6da6c30b80f0
parent 9c4d0695e9d0b1e551a93b179a373e2bcf469f06

qemu: Implement qemu_system_off via semihosting.

This makes the PSCI SYSTEM_OFF call work on QEMU. It assumes that QEMU has
semihosting enabled, but that is already assumed by the image loader.

Signed-off-by: Andrew Walbran <qwandor@google.com>
Change-Id: I0fb7cf7909262b675c3143efeac07f4d60730b03

plat/qemu/common/qemu_pm.c

diff --git a/plat/qemu/common/qemu_pm.c b/plat/qemu/common/qemu_pm.c
index a199688..116211c 100644
--- a/plat/qemu/common/qemu_pm.c
+++ b/plat/qemu/common/qemu_pm.c
@@ -10,10 +10,13 @@
 #include <arch_helpers.h>
 #include <common/debug.h>
 #include <lib/psci/psci.h>
+#include <lib/semihosting.h>
 #include <plat/common/platform.h>
 
 #include "qemu_private.h"
 
+#define ADP_STOPPED_APPLICATION_EXIT 0x20026
+
 /*
  * The secure entry point to be used on warm reset.
  */
@@ -191,7 +194,8 @@
  ******************************************************************************/
 static void __dead2 qemu_system_off(void)
 {
-	ERROR("QEMU System Off: operation not handled.\n");
+	semihosting_exit(ADP_STOPPED_APPLICATION_EXIT, 0);
+	ERROR("QEMU System Off: semihosting call unexpectedly returned.\n");
 	panic();
 }
 

plat/qemu/qemu/platform.mk

diff --git a/plat/qemu/qemu/platform.mk b/plat/qemu/qemu/platform.mk
index eaeb72c..b95bf5a 100644
--- a/plat/qemu/qemu/platform.mk
+++ b/plat/qemu/qemu/platform.mk
@@ -151,6 +151,8 @@
 BL31_SOURCES		+=	lib/cpus/aarch64/aem_generic.S		\
 				lib/cpus/aarch64/cortex_a53.S		\
 				lib/cpus/aarch64/cortex_a57.S		\
+				lib/semihosting/semihosting.c		\
+				lib/semihosting/${ARCH}/semihosting_call.S \
 				plat/common/plat_psci_common.c		\
 				${PLAT_QEMU_COMMON_PATH}/qemu_pm.c			\
 				${PLAT_QEMU_COMMON_PATH}/topology.c			\

plat/qemu/qemu_sbsa/platform.mk

diff --git a/plat/qemu/qemu_sbsa/platform.mk b/plat/qemu/qemu_sbsa/platform.mk
index f34c7e1..51832d0 100644
--- a/plat/qemu/qemu_sbsa/platform.mk
+++ b/plat/qemu/qemu_sbsa/platform.mk
@@ -71,6 +71,8 @@
 BL31_SOURCES		+=	lib/cpus/aarch64/aem_generic.S			\
 				lib/cpus/aarch64/cortex_a53.S			\
 				lib/cpus/aarch64/cortex_a57.S			\
+				lib/semihosting/semihosting.c			\
+				lib/semihosting/${ARCH}/semihosting_call.S	\
 				plat/common/plat_psci_common.c			\
 				${PLAT_QEMU_COMMON_PATH}/qemu_pm.c		\
 				${PLAT_QEMU_COMMON_PATH}/topology.c		\